howes



((((( 1.) 2 Sheets-Sheet 2.

F. H. HOWES.

NUT LOCK.

- No.' 341,145. Patented May 4, 1886.

UNITED STATES PATENT OEEIcE.

FRANK H. HOVES, OF EAST ORANGE, NEV JERSEY.

NUT-LOCK.

SPECIFICATION forming part of Letters Patent No. 341,145, dated May4,1886.

Application filed November 1B, IESS. Serial No. 183,157.

To @ZZ whom t may concern.-

Be it known that I, FRANK H. HowEs, of

' East Orange7 New Jersey, have invented a certain Improvement in Boltsand Nuts,l of which the following is a specification.

This improvement relates to the type of bolts and nuts havingscrew-threads relatively so proportioned as to conflict with and abradeeach other when the nut is applied to the bolt, and to thereby cause thenut to acquire a firm grip upon the bolt. This result has heretoforebeen attained by the employment in the bolt and :nut of threads ofdi'erent pitches, and also by the employment of threads differing in theangles of their sides of the contour of their cross-sections either fromeach other or from the grooves which they are intended to engage, and itis a result which has also in a measure been produced whenever atight-fitting nut has been applied to a bolt.

The present invention consists in the employment, in a bolt and nut,respectively, of screw-threads which are truncated or rounded upon theirapices, and which are alike in the angles of their sides and in thecontour of their cross-sections, and which are in a prescribed degreewider than the portions of the grooves in which they are respectively tobe contained, the remaining` portions or bottoms of the groovespresenting cavities for the reception of the metal upset by the pressureof the sides of the threads upon each other.

The accompanying drawings, illustrating a bolt and nut embodying theinvention, are as follows:

Figure l is an elevation of the bolt, showing it just entered into anut, which is represented in axial section. Fig. 2 is an axial sectionof a bolt and Inut, illustrating the effect of the complete applicationof the 'nut to the bolt. Fig. 3 is a longitudinal section of portions ofa bolt and a nut, illustrating modifications in the forms of the threadsin cross-section. Fig. 4 is an axial section upon a large scale, showingthe end portion of the bolt `just entering the nut; and Fig. 5 is asimilar section showing the nut and portion of the bolt in fullengagement.

The drawings represent a bolt, A, provided (Model.)

with a truncated screw-thread, a, or with a thread having a roundedapex, a. The sides of the thread have the usual angle of sixty degrees.The nut Bis also provided with a truncated thread, b, or with a threadhaving the rounded apex b. The bolt is provided either with the V-shapedgroove C, or the groove may. have the dat or rounded bottom C or Cf.Similarly the nut may have the V-shaped groove D or the flat orround-bottomedl groove D or D2. In either case the groove is madesufficiently deep to present at the bottom the cavity E for thereception of the metal displaced by the pressure of the sides of thethreads upon each other in the act of applying the nut to the bolt.

The difference between the thickness of any part of the thread and thecorresponding part of the groove by which it is to be engaged will ofcourse be varied according to the kind of metal -which is employed, andalso according to the size of the bolt and nut. In any case thedimensions of the cavities E at the bottom of the grooves must beproportioned with reference to affording room for the dow of thequantity of metal upset by the act 0f applying the nut to the bolt. Bythe observance of this rule the proportions will readily be arrived atin practice by those skilled in the 1nanufacture of ordinary bolts andnuts.

It will be seen, as illustrated in Fig. 4, that in applying the nut tothe bolt the conict of the threads does not begin until the bolt hasbeen turned nearly one complete revolution upon its axis after its firstengagement with the nut. At the extreme end of the bolt the thread isincomplete, and it is not'until the bolt is so far turned as to bringthe complete thread of the bolt into engagement with the nut that thepressure of the sides of the threads upon each other begins. As therotating movement progresses the extent of pressure, ofcourse,increases, but with such progression there is increased holdofthe nut-threads upon the bolt threads, which is sufficient to maintainthe continued engagement of the nut with the bolt, and to eiiect theupsetting and flow of metal into the cavities provided for itsreceptions at the bottoms of the" grooves approximately, as illustratedin Fig. 5, and suiiioient depth to afford at their bottoms 1o by thedotted lines x and rv intersecting cavities for the reception of themetal upset both Figs. 4 and 5. by the pressure of the sides of thethreads Vhat is claimed as the invention isupon each other in the not ofapplying the nut FR ANK H. HOWES. Vitnesses:

R. C. HoWEs, M. L. ADAMs.

Abolt and nut provided with screw-threads to the bolt. of likepitch andlike angles upon their sides, but of greater thickness than the Width ofthe portions of the grooves in which they are to be engaged, andprovided with grooves of l

